Alloying hexagonal/orthorhombic Ga<sub>2</sub>O<sub>3</sub> with Al<sub>2</sub>O<sub>3</sub>

ORAL

Abstract

Ga2O3 is a wide-band-gap semiconductor with promising applications in high-power devices and UV photodetectors. It occurs in several polymorphs, with monoclinic β-gallia the thermodynamically stable phase. Other polymorphs of Ga2O3 can be stabilized as well, but are less studied. The ε- and κ-polymorphs are of interest as they possess ferroelectric properties and exhibit large spontaneous electrical polarizations.
Here we use density functional theory with hybrid functionals to elucidate how alloying with Al2O3 can be used to modify the structural and electronic properties of Ga2O3. We focus on tuning lattice constants and band gaps as a function of Al concentration. We also report the absolute alignments of valence and conduction bands. Our quantitative results can be used to guide experimental design of new devices.

*Work supported by the Office of Naval Research through the Naval Research Laboratory’s Basic Research Program.

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Presenters

  • Sierra Seacat

    • Department of Physics & Astronomy, University of Kansas

Authors

  • Sierra Seacat

    • Department of Physics & Astronomy, University of Kansas

  • John Lyons

    • Center for Computational Materials Science, United States Naval Research Laboratory
    • Center for Computational Materials Science, US Naval Research Laboratory

  • Hartwin Peelaers

    • Department of Physics and Astronomy, University of Kansas
    • Univ of Kansas
    • Department of Physics & Astronomy, University of Kansas